Time delay relay



1937- B. o. BROWNE 2,090,995

TIME DELAY RELAY ,Filed Aug. 1, 1936 5 Sheets-Sheet l INVENTOR B. O.BROWNE ATTORNEY Patented Aug. 24, 1937 UNiTED STATES PATENT OFFICE TIMEDELAY RELAY Application August 1, 1936, Serial No. 93,803

10 Claims.

H the guard member.

Another feature resides in means for operating the contact controllingmember.

In the drawings,

Fig. 1 is a rear elevational view, partly in section, of the relay andwith part of the structure removed;

Fig. 2 is a top view, partly in section, taken on the line 2-2 in Fig.1;

Fig. 3 is a side elevational view, partly in section, of the relay andviewed from the right of Fig. 1;

Fig. t is a top view of a portion of the structure and taken on the lineof Fig. 3;

Fig. 5 is a rear view, partly in section, of an upper central portion ofthe relay;

Figs. 6 and .7 are views corresponding to Fig. 1 but with. certainportions removed and showing the relay operated two positions, Fig. 6being a first operated position and Fig. 7 a second position; and

. 8 is a view, partly in section, of the lower portion of Fig. '7 and asviewed from the right of Fig. 7 on the line 38.

In electrical apparatus it is sometimes found iecessary or desirable toprovide circuit contro g means that will operate at the end of apredetermined Tod of time after certain other switcl" us are performed.For in- -n electrical apparatus in which vacuum g; are employed, it isfound necessary in some ins tances, in order to prevent breakdown of thei to delay the application of plate current hes for a predete- -inedperiod of time after filament current been applied. In

ele

.11 some cases a longer time period than in others uired. inventionprovides means for perfo..ming the function above-mentioned.

The relay mechanism as shown in the drawings particular reference toFigs. 1, 2, and 3 mounte in a casing 3 comprising a front plate 2, a top3, a rear wall 4 and side walls 5 and 6. A base l is shown as beingcomposed of insulating material. The base 7 is not attached to parts ofthe casing, but serves as a closure for an open end of the casing and asa base plate and terminal block for parts of the relay, the relay beingheld in place within the casing l by means of screws, not shown, butwhich pass through the front wall 2, then through spacers 8-8 and into aportion of the relay structure. Spaced studs 5 are provided on the frontwall 2 so that the relay may be attached to a suitable support (notshown). Spaced binding post terminals ID are secured in the base plate iand project below the lower surface of the base plate I to serve asmeans for connecting circuit wires to the relay. The relay structure isprovided with spaced posts l i which project downward into engagementwith the upper surface of the base plate I and which receive machinescrews l 2 to hold the relay structure securely mounted on the baseplate 1. Secured to the upper surface of the base plate 1 by means ofone of the terminals H3 is a U-shaped support l3 and having two upwardlyprojecting arms 14 upon which are secured leg portions of a U-shapedspring l5 as shown in Fig. 4. The leg portions of the U-shaped spring i5pass beyond their points of support on the arms i4 and have attached totheir free ends a laminated U-shaped plate it having its closed end i!extending between the leg portions of the U-shaped flat spring I5 andtoward the closed end 18 of the spring 15. The laminated U-shaped plateto has projections 9l9 on its inner end and extending between theprojections l9 and clamped between the laminations of the U-shaped plateI 6 is a knife edge 20 which may be a separate member or a portionextending inward from the free ends of the legs of the fiat U-shapedspring l5 and disposed between the laminations of the U-shaped plate l6.Between the knife edge 20 and an inner edge portion 25 of the closed endit of the flat U-shaped spring i5 is a bowed spring 22 which serves tosnap the closed end of the U-shaped flat spring 55 upward or downward ina quick-operating snap action movement when the U-shaped laminated platei6 is operated and in a direction opposite to the direction of movementof the laminated U-Sh21pd plate I6. On the closed end of the U-shapedspring l5 and disposed on the lower surface thereof is a rectangular bar23 of conducting material which serves to bridge two spaced contacts24-424 when the closed end of the U-shaped spring 15 is moved downward.The spaced contacts are supported on posts 2525 which rest against theupper surface of the base plate l and form a part of two of the bindingposts It and to which wires of the circuitto be controlled may beattached. An arm 25 extending upwardly from one end of the U-shapedsupport l3 serves as a stop for the closed end of the laminated U-shapedplate it, the arm 26 having a notch 2'! on its upper end. and forming anoperating space in which the closed end of the laminated U-shaped plateit may operate upward and downward to a limited extent, the extent ofmovement being governed by the width of the notch 27. Across the uppersurface of the closed end of the U-shaped spring is a rectangular bar 28corresponding to the bar 23 on the lower surface and which may be madeof either conducting or insulating material. Extending upward from theupper surface of the base plate 1 and secured thereto is a machine screw29. Surrounding the shank of the machine screw 29 and engaging the uppersurface or the base plate l. is .a tubular member til. Supported on theupper end of the tubular member 353 and engaged by the head of themachine screw 29 is a flanged insulating member M, the insulating member3i having a flange 32. directly under the head of the machine screw 29.The flange 32 is disposed adjacent the upper surface of the bar 23 andserves as a stop to limit the upward movement of the closed free end ofthe U-shaped spring 55 and thereby serving to limit upward movement ofthe movable contact of the snap switch.

The snap switch arrangement described is operated by means of a plunger33 which is threaded on its upper end to receive a ring nut t l, aplunger pin 35 and a lock nut 35. The plunger 33 is operated by means ofan electromagnetic device 3? and extends upward through a movable plug38 of the electromagnetic device :l'l and which operates within acylindrical core 39. The plug 38 is made of magnetic material and iscomparatively heavy and is longitudinally bored to freely receive theplunger 33, the bore being of suflicient diameter to permit freemovement of the plunger 33 within the plug 38. The lowermost end of theplunger 33 is threaded to receive a ring nut 4E) and is reduced indiameter to receive a tubular member ii of insulating material, thetubular member ll being made of some substantially strong and hardinsulating material such for instance as porcelain or Isolantite. Thetubular member 3! of insulating material is'enlarged on each end toprovide flanges -32 and i3 and a cen tral portion M of smaller diameterthan the flanged ends. The reduced central portion 44 on the tubularmember ii of insulating material passes upward between the leg portionsof the laminated U-shaped plate it. The flange d2 of the insulatingmember ll engages embossings it- 55 on the upper lamination oi theU-shaped plate it when the plunger 33 is in a down position. The flanged3 engages embossings 56lfi, provided on the lower lamination of thelaminated U-shaped plate it, when the plunger 33 is moved to an upposition. When the plunger 33 is in a down position as shown in Figs. 3and 6, the closed end of the laminated U-shaped plate is is in a downposition. When the closed end of the laminated U-shaped plate it ismoving to a down position spring tension is developed in the bowedspring 22. When the U-shaped plate it is moved to its down position, thebowed spring 22 by reason of the spring action developed therein snapsthe closed end portion of the U-shaped spring member If: upwardly with aquick snap action so that the rectangular bar 28 is moved upward againstthe flange 32 of the stop member 35. The downward movement of thelaminated U-shaped plate i6 is limited by the slot 27 in the arm 28. Inthe positions above mentioned and as shown in Figs. 3 and 6, therectangular bar-23 of conducting material is moved away from the spacedcontacts 2 i2A-. The circuit controlled by this portion of the relay,therefore, is opened.

The electromagnetic device 31 comprises an operating coil ll, a movableplug 38 and a hollow core 39. The operating coil ll is enclosed in acasing 58 from which the posts I I extend downwardly to the uppersurface of the base plate l. The screws, not shown, but which extendthrough the front plate 2 of the device and through the spacers 8-8extend into threaded embossings 49 in the casing Q8 of theelectromagnetic device 3'3. Secured to the top of the casing d8 of theelectro magnetic device by means of screws 5E3, shown in Fig. 2, is anapertured plate M, the plate being apertured to permit extensiontherethrough of the plunger 33. The upper portion of the plug 38 ofmagnetic material is longitudinally bored upper end of the spring 52bears against a washer 3 it held in place on the plunger 33 by means ofthe ring nut t l. When the energizing coil ll of the electromagneticdevice 37 is energized, the

plug 38 is drawn upward within the core 39 and r compresses the spring52. The spring 52 tends to move the plunger 33 upwardly. The extent ofupward movement of the plunger 33, however, is limited by means of amovable guard t l which is driven with time across the path of movementof the pin iii-i on upper end of the plunger 33. The guard t l,therefore, stops the upward movement of the plimgerfit after it hasmoved to a small extent. The plug 35, however, is moved upward againstthe spring 52 by the magnetic attraction developed in theelectromagnetic device Sll through the energizing coil ll and the coreThe spring 52, therefore, is compressed to an extent determined by themagnetic pull of the electromagnetic device, and the spring pressuredeveloped in the spring 52 is continually urging the plunger 33 upwardagainst the guard 53. The guard 56 is a metal plate L-shaped incross-section and one of the leg portions is attached to an arcuateskeleton frame which is movably supported on a bolt 55. The other legportion of the guard is bowed transverse to the axis of the bolt 55 andextends across the top of the pin 35. The arcuate skeleton frame 56 withthe guard 5 5 attached thereto is journaled on the bolt 55. The bolt 55is supported on a pivoted arm 51!, the arm 5's being pivotally supportedat a point 58 on the stationary support 59. The outer edge of thearcuate skeleton frame 55 is knurled at Gil as shown in Figs. 2 and 3. Acoil spring 35 supported on the jcurnaled portion of the arcuateskeleton frame 56 on the bolt is provided to continually urge thearcuate skeleton frame 55 in a clockwise direction, the spring 8! havingone end 52 fastened in the free end of the arm 571 and the other end 63being hooked around a leg portion 65 of the arcuate skeleton frame 55.Throughout this specification, when direction of movement of a part isstated as being in a clockwise or a counterclockwise direction thedire-ction mentioned is to be considered as when the relay is viewedfrom the back as shown in Figs. 1, 5, 6, and '7. An adjustable stop isprovided to limit the extent of clockwise movement of the arcuateskeleton frame 55. The adjustable stop comprises a segmental plate 65and an L-shaped arm The segmental plate 635 is attached to the pivotedarm 51 and has teeth 61 formed on its outer edge and a heel G8, the heel68 being adapted to rest on the plate 5|. The L-shaped arm 56 isjournaled on the bolt 55 and has a leg portion 39 extending above theteeth 6'! on the segmental plate 65 and into the path of return movementof the skeleton frame 56. A wire spring 'N] as shown in Fig. 3 isprovided on the free end of the leg portion d9 of the L-shaped arm 65.The wire spring l extends backward from this point beneath the legportion t9 and through a slot ii in the arm 36 and extends beyond thesurface of the arm 66 a sufficient distance to be readily engaged by aperson desiring to adjust the apparatus. The free portion of the wirespring lb adjacent the point where it passes through the slot '55normally rests between the teeth 6'5 of the segmental plate 65 to retainthe L-shaped arm 55 in a requi ed position. The spring "fill may bereleased from engagement with the teeth 6? by manually pressing the freeend upward in the slot H and the arm 56 may then be swung in a requireddirection and the free end of the spring it released again so that thespring sets into engagement with the teeth 67 in the re quired position.Since the arcuate skeleton frame 56 is continually being urged by thespring in a clockwise direction and, therefore, against the leg portion69 of the L-shaped arm 66 movement of the arm results in a correspondingmovement of the arcuate skeleton frame 56. Since the guard 56 is carriedby the frame 5% a corresponding movement of the guard 54 is alsoobtained. Movement of the arm 55, therefore, results in changing theeffective length of the skeleton frame 55 and the effective length ofthe guard 54 and consequently results in a change in the timecharacteristic of the relay.

i /hen the electroniagnet 3i is energized to raise the plunger 33 thepin 35 is brought upward against the guard 54 and the upward pressure ofthe pin 35 against the guard swings the arm 5? upwardly about its pivotpoint 53. In this 2 movement the arcuate skeleton frame 55 is raised sothat the knurled portion fit is brought into engagement with africtional drive wheel 12 driven by and forming part of a synchronousmotor The synchronous motor '63, preferably, is

a self-starting type synchronous motor and is controlled by means of aswitch not shown but located at some remote point. One of the lead wiresfor the field winding 14 of the motor 73 is connected to a pair ofcontact springs 15 which are normally closed. The springs 5 are normallyheld closed by means of a spring having a button ll serving to press thecontact springs 15 together. A free end it of the spring l6 extendsdownward to a point directly above the line of travel of the pin 35 onthe plunger 33 so that when the plunger 33 is raised to full extent thepin 35 will engage the free end 78 and raise the spring 16 sufiicient toallow separation of the spring contacts l5.

When the device is to be operated, circuits are closed for theelectromagnet 31 and the synchronous motor '13. This might be forinstance when current is applied to the filament of a vacuum tube. Themotor l3 then begins to operate and rotates the frictional drivingmember 12 in a clockwise direction. When the electromagnet 31 isenergized, the plug 38 is raised within the core against the spring 52,compressing the spring. By this action the plunger 33 is raised so thatthe pin 35 is brought into engagement with the guard 54. Pressureagainst the guard 54 causes the arm 5? to swing upward about its pivotpoint 58 and the arcuate shaped skeleton frame 56 is brought intoengagement with the frictional driving member The arcuate shapedskeleton frame therefore, is rotated in a counter-clockwise direction bymeans of the synchronous motor 13. The arcuate skeleton frame 56,therefore, carries the guard 54, beyond the path of movement of the pin35 on the plunger 33. When the guard is moved beyond the path ofmovement of the pin 35, the spring 52 forces the plunger 33 upward tofull extent of its traverse. In this upward movement the pin 35 engagesthe free end "iii of the spring 16 and moves the spring 16 upward sothat the contact springs f5 are permitted to open. Opening of the springcontacts 15 breaks the circuit of the synchronous motor 13 and the motorstops. When the plunger 33 is rising to full extent of its traverse, theflange 43 of the insulating member 4| engages the embossings 46 of theU-shaped plate l5 and swings the U -shaped plate i5 upwardly. Upwardmovement of the U-shaped plate l6 as it passes over dead ce ter developsspring tension in the bowed sp and the tension developed in this bowedspring 22 forces the free end of the U-shaped member l5 downwardly witha quick snap action so that the rectangular bar 23 of conductingmaterial. is brought down into engagement with the spaced contacts24-24. The spaced contacts 24-24 may be connected in a circuit leadingto a plate of a vacuum tube. The plate circuit of the tube, therefore,is closed with a quick snap action by the bridging of the contacts 24-24by the rectangular plate 23 of conducting material. It is obvious thatthe contacts 24-44 might be included in any circuit desired to becontrolled by the time delay device of this invention.

To open the circuit in which the contacts 2424 are included, it is onlynecessary to cut off the supply of current to the operating coil 41 ofthe electromagnetic device 31. When the electromagnetic device 3? isdeenergized, the plug 38 is released and drops downwardly against theupper surface of the flange 42 of the insulating member and carries theplunger 33 downward so that the lower surface of the flange 42 strikesagainst the embossings d5 of the U-shaped plate Hi. This action forcesthe U-shaped plate it downwardly and as the Ushaped plate l6 passesacross dead center position it develops spring tension in the bowedspring 22 and this spring tension in the bowed spring 22 forces the freeend of the Ll shaped member l 5 upwardly with a quick snap action sothat the rectangular bar 23 of conducting material is quickly moved awayfrom the spaced contacts 24-24. The circuit controlled by the device,therefore, is quickly opened. When the free end of the U-shaped memberl5 moves upwardly, the rectangular plate 28 on the upper surface of theU-shaped member l5 strikes against the flange 32 of the insulatingmember 3!. The flange 32 of the insulating member 3!, therefore, servesas a stop to limit upward movement of the closed end of the U-shapedmember The length of the time period between the time of starting of thedevice and the bridging of the contacts 21-24 is determined by the speedof the motor 73, the driving ratio between the frictional driving memberl2 and the arcuate shaped skeleton frame 56 and the effective lengths ofthe arcuate shaped skeleton frame 56 and the guard 5 The effectivelengths of the arcuate shaped skeleton frame 56 and the guard 54 may bechanged'by moving the stop arm 66 against the end of the arcuate shapedskeleton frame 56 and moving the skeleton frame 56 so that the guard 54is moved across the path of movement of the pin 35. For instance theguard 5t. may be moved so that the central or any other predeterminedportion of the guard M is in the line of movement of the pin 35. Whenthe synchronous 7 motor '53, therefore, is operated and theelectromagnetic device 3'! is energized, the pin is brought upward intoengagement with the guard 54 at the predetermined point and the motor itdrives the arcuate skeleton frame at and the guard 5 is carried from thepredetermined point in a counter-clockwise direction until it moves outof the path of movement of the pin 35. When the guard 55 is moved out ofthe path of movement of the pin 35, the contacts l b-2 are quicklybridged by the rectangular bar 23 of conducting material. When the guard5 is moved beyond the path of movement of the pin 35 the upward pressureserving to hold the arcuate shaped skeleton frame 56 against thefrictional driving member '12 is no longer effective to hold theseelements in engagement and the assembly of elements carried by thepivoted arm 5? drops by gravity to normal position with the heel G8resting on the plate 55. The arcuate shaped skeleton frame 58 and theguard 55, however, are prevented by the pin 35 from returning to normalor starting position, the pin 35 being across the path of returnmovement of the guard 5 Deenergization of the electromagnet 37 resultsin release of the plunger Upon release of the plunger 33, the pin 35 iscarried downward out of the path of return movement of the guard 54. Thespring pressure developed in the coil spring 6i during the rotation ofthe arcuate skeleton frame 56 then returns the skeleton frame 56 and theguard 55 to starting position, the extent of return-movement being theextent permitted by the stoparm 56. If the stop arm 66 has been set partway upward of the segmental plate 85, for instance, the guard 5% will bemoved to about half its length across the path of movement of the pin35. With this setting of the stop arm '56, the device will have acomparatively short time delay characteristic. To lengthen the timedelay characteristic of the device it is only necessary to release thewire spring is from engage ment with the teeth 6? of the segmental plate{55 and then swing the stop arm 66 downward to a predetermined point andrelease the wire spring it! so that it engages teeth iil at a lowerpoint on the segmental plate '55. In this position the guard 5 will havea greater effective length than when the stop arm 6% is in the full lineposition shown in Fig. 1. The stop arm 66 for instance may be set in thedotted line position shown in Fig. 1 so that the time delaycharacteristic of the relay will be at the maximum obtainable in thestructure. To shorten the characteristic it is only necessary to releasethe spring 78 from engagement with the teeth ti and swing the stop arm66 upward along the curved edge of the segmental plate and release thespring if! to set into the teeth 61 in a required position.

What is claimed is:

1. A time delay relay comprising a movable contact operating member, amovable guard operating in the path of movement of said contactoperating member and driving means to move said guard from the path ofmovement of said contact operating member at apredetermined time,characterized in this, that an electromagnet moves said movable contactoperating member against said guard, lifts said guard into engagecntwith said driving means and compresses a spring against said movablecontact operating member, to further move said contact operating memberwhen guard is driven by said driving means out of the path of movementof said contact operating member.

2. A time delay relay, in accordance with claim 1, and in which saidguard comprises an arcuate frame carrying a curved guard portionoperating in the path of movement of said contact operating member.

3. A time delay relay, in accordance with claim 1, and in which saidcontact operating member comprises a longitudinally movable plungerhaving an end brought into engagement with said guard.

A time delay relay comprising in combination, a fixed contact, a movablecontact, a contact operating member engaging said movable contact, aguard operating in the path of movement of said contact operatingmember, driving means for said guard, and electromagnetic means to movesaid contact operating member against said guard and to move said guardinto engagement with said driving means.

5. A time delay relay comprising in combination, a fixed contact, amovable contact, a contact operating plunger operating to move saidmovable contact, a guard operating in the path of movement of saidcontact operating plunger, driving means for said guard, a coil springon said plunger and a solenoid operated to move said plunger againstsaid guard to move said guard into engagement with said driving meansand compress said spring, said spring operating to further move saidplunger when said guard is moved by said driving means out of the pathof movement of said plunger.

6. A time delay relay comprising a solenoid, a

spring compressed by means of said solenoid, a

contact operating plunger carrying said spring and operated by means ofsaid spring, a guard operating in the path of movement of said contactoperating plunger, driving means operating with time to drive said guardout of the path of movement of said contact operating plunger andcontacts controlled by means of said contact operating plunger.

7. A time delay relay comprising an electromagnetic device, a tubulararmature operated by means of said electromagnetic device, a plungerloosely carrying said armature, said plunger extending axially throughsaid armature, a spring supported on said plunger and bearing againstsaid armature and said plunger to move said plunger relative to saidarmature, said armature when attracted operating to compress saidspring, a movable guard operated across the path of movement of saidplunger, driving means to drive said guard out of the path of movementof said plunger and contacts operated by means of said plunger when saidguard is removed from the path of movement of said plunger.

8. A time delay relay comprising an electromagnet, a plunger, anarmature operated on said plunger by means of said electromagnet, aspring on said plunger compressed by means of said armature andoperating to apply driving pressure to said plunger, a snap switchoperated by means of said plunger, contact springs controlled by saidplunger, a movable guard operating in the path of movement of saidplunger and driving means for said guard, said driving means operatingwith time to drive said guard out of the path of movement of saidplunger.

9. A time delay relay comprising an electro magnet, a plunger, switchelements controlled by means of said plunger, an armature operated onsaid plunger by means of said electromagnet, a compressible spring saidplunger and operating said plunger, said spring being compressed bymeans of said armature when the electromagnet is energized, a movableguard operating in the path of movement of said plunger, a synchronousmotor operating to drive said guard out of the path of movement of saidplunger and an adjustable stop member to control the effective length ofsaid guard.

10. A time delay relay comprising a plunger, switch elements operated bymeans of said plunger, a spring on said plunger to operate said plunger,a movable guard operating in the path of movement of said plunger, amovable frame carrying said guard, driving means for said frame, anelectromagnetic device operating to lift said frame into engagement withsaid driving means and an adjustable stop arm engaging said frame andmanually operated to change the effective lengths of said frame and saidguard.

BENNIE O. BROWNE.

